Electric switch



Jan. 21, 1941.

H c. BOLLEY ELECTRIC SWITCH Filed Feb. 24. 1943 HfiSC/Yfl c aouzrATTORNEY Patented Jan. 21, 1947 ELECTRIC SWITCH Herschel C. Bolley,Bronson, Micln, assignor to g H. A. Douglas Mfg. 00., Bronson, Mich., acorporation of Michigan Application February 24, 1943, Serial No.476,981

This invention relates generally to electrical switches and, moreparticularly, to switches adapted for use on automotive vehicles and gunmounts in connection with ordnance equipment.

One particular object of the invention is to provide a switch in whichthe mechanism thereof, including the switch and casing therefor, aresubstantially sealed within a housing so that the switch is protectedfrom injury and foreign matter and fiuid are substantially preventedfrom entering and interfering with the operation of the switch.

Another object is to provide improved means for permanently securing aswitch casing within a housing and preventing rotation between the two.

A further object is to provide improved means for locking the operationmeans for the switch in place.

Other objects and advantages of the invention will be apparent afterconsidering the description hereinafter set forth in connection with thedrawing annexed hereto.

In the drawing:

Figure 1 is a vertical section taken through the switch, the housing,means for connecting the two together, and other means whereby toclearly illustrate certain details of construction;

Figure 2 is a transverse section taken substantially on line 2-2 ofFigure 1, portions of which are broken away whereby to better illustratecertain parts of the switch;

Figure 3 is a section more or less corresponding to the section shown inFigure 2; showing the switch in a position diflerent from thatillustrated in Figure 2;

Figure 4 is a bottom view-of the switch and the housing with the coverremoved from the latter; and

Figure 5 is a view showing the manner in which the conduits entering thehousing for the switch casing are substantially sealed in place.

As noted above, one object of the invention is to provide a more or lessfluid type enclosure for an electric switch and this has been foundnecessarybecause it has been found that salt water and dust have adeteriorating effect upon the operation of the switch when'used onvehicles in combat zones around salt water and in desert areas. Theprinciples of design and construction embodied in the present switchhave proven very successful in actual combat zones and areas.

The housing I provides an enclosure for the switch casing 2 and, thehousing and easing are preferably permanently secured together by a4Claims. (01.200-6) tubular element 3. The housing I is fashioned totake the shape of a cup and is constructed of sheet metal. Theswitch'casing 2 is also constructed of sheet metal and is similar inshape but of a size to fit concentrically and entirely within theconfines of the housing I. The switch casing 2 may be provided with anydesirable means for making and breaking an electric circuit.

As herein illustrated the open end of the casing is preferably closedoff by a composite contact carrier assembly 4, which is fixed in placeby deforming fingers provided on the casing 2 over and upon the outersurface of the carrier assembly 4. The carrier assembly 4 may beprovided with a plurality of rivet contact means 5, the innerextremities of which provide contact surfaces and the outer extremitiesof which are flanged over and upon the base portions of terminal posts 6as clearly illustrated in Figure 1.

The switch mechanism within the casing 2 includes actuated means Isupporting a bridge carrier 8. The bridge carrier 8 is held againstrotation with respect to the,actuatingmeans 1 by means of tonguesprovided on the actuating means which project into suitable notchesprovided therefor in the periphery of the carrier. The carrier 8 ispreferably provided with a pair of spaced apart bridge means 9 and II]which are secured for movement with the carrier 8 by means of lugsprovided on the bridge means which project through suitable aperturesprovided therefor in the carrier as illustrated in Fi ures 1 through 3.Each of the bridg means 8 and I0 is preferably provided with a pair ofrounded bosses forming contacts which are adapted to cooperate with thevarious rivet contact means 5 in the manner desired to control certainelectrical circuits.

The bridge means 9 and Ill carried by the carrier 8 are urged rearwardlytoward the contact carrier assembly means 4 and the actuated means Iforwardly in an opposite direction by means of a helical spring ll. Asclearly shown one extremity of the spring bears against the carrier 8and the opposite extremity receives an inwardly extending centrallydisposed boss portion provided in the base of the actuated means 1whereby to hold the spring in a predetermined position so that theenergy exerted thereby is properly distributed to provide awell-balanced construction. It will be noted that the arrangement issuch that the spring cannot engage the lugs p vi d on the bridge means 8and In which project through the carrier 8.

Means are provided for predetermining the 011" and "oif" positions ofthe actuated means and means associated therewith with respect tothe'rivet contacts 5. The positioning as herein shown is preferablyaccomplished by providing the base of the actuated means 1 with aplurality of depressions or seats l3, certain of which are illustratedin Figure 1. The base or end wall of the switch casing 2 is providedwith a plurality of inwardly extending detents l2 which are adapted tocooperate with the seats l3 in the desired manner. It will be noted thatthe seats l3 and detents 12 are so constructed and arranged that thebase of the actuated means 1 and the end wall of the switch casing 2 areheld in spaced apart parallel relation so as to alleviate friction.

The operating means of the switch includes a. relatively short shaft 14which is rotatably mounted in the bore l5 of the tubular element 3. Theinner extremity of the shaft is connected to the actuated means I in anydesirable manner, but as herein illustrated, the shaft is provided witha tongue portion [6 which projects into a rectangular aperture I!provided in the base of the centrally disposed boss portion of the meansI. It will be noted that the inner extremity of the tubular element 3 isprovided with a tubular portion i8 which extends through apertures l9and 20 provided in the end walls of the housing and casing and isflanged over and upon the inner surface of the end wall of the casing 2for permanently securing the housing, casing, and tubular element inassembly. The casing 2 is held against rotary movement with respect tothe housing I by providing the end, wall of the housing with an inwardlyextending projection 2| which fits into a hole or recess 22 provided inthe end wall of the casing 2.

The switch may be mounted as desired, but is preferably adapted to besecured to the rear side of an instrument panel mounting so that thethreaded portion of the tubular element projects forwardly through asuitable aperture provided therefor in the, mounting with the shoulder23 of the element engaging the rear side of the mounting and so that anut which cooperates with the threads on the element engages the frontside of the mounting.

Means are provided whereby to prevent dust, dirt or other foreign matterfrom entering the housing and switch casing through the tubular element3 and this is accomplished by providing the outer extremity of thetubular element 3 with annular recesses 24, 25 and 26, the diameters ofwhich progressively decrease in the order named. The recess 26 slidablyreceives a cylindrical enlargement 21 provided on the shaft l4 wherebyto limit inward movement of the shaft. A fiber washer 28 or theequivalent is disposed in the recess 25 between the recesses 24 and 26and is pressed into place by a washer 29, the latter of which is securedin position by flanging over some metal of the element upon the washer.The washer is compressed to such an extent that portions thereof areforced into intimate engagement with the walls of the recess 25 and thecylindrical surface of the shaft M including a side of the enlargement21. This arrangement, in addition to excluding foreign matter, providesmeans for holding the shaft against outward movement. Obviously, iffound desirable the washer 28 may be impregnated with graphite or otherdesirable lubricant.

The recess 24 provides clearance so that a key, screw driver, or theequivalent, may enter the notch 30 provided adjacent the outer extremity4 of the shaft ll. A pivotal cover conceals the shaft I 4 and providesadditional means for excluding foreign matter from entering the switchand housing. The cover may be provided with a raised portion 3| wherebyto facilitate pivotal movement of the cover.

To operate the switch, it is merely necessary to insert a key into theoperating means or shaft i4 and rotate same including the actuated meansone way or the other so that the bridge means 9 and ill will cooperatewith the rivet contacts 5 in the desired manner to control the variouselectrical circuits. No reference is made as to which rivet contacts areengaged by the bridge means 9 and Ill for the reason that the inventionis not directed to the contacts, bridge means or circuits controlledthereby.

Additional means are provided whereby to prevent fluid and foreignmatter from entering the switch housing and switch casing and will nowbe described. The free extremity of the switch housing I is preferablyprovided with a radially extending flange 32 which is provided with aplurality, preferably three, equally spaced apart apertures 33. The openend of the housing I is closed off by an annular cover 34. A rubberwasher 35 or the equivalent is disposed between the flange 32 and thatportion of the cover opposite the flange 32. Clamping bolts 36 passthrough apertures provided therefor in the cover and washer and throughthe apertures 33 in the flange '32 whereby to seal off the open end ofthe housing. This arrangement provides a shield or guard for the switchcasing, including the takeoff terminals 6, and at the same time providesa substantially fluid-tight enclosure for the switch casing.

The conductor wires or leads which are adapted to be connected to thetake-off terminals 6 are preferably encased in conduits which are.adapted to enter the side wall of the housing 1. One of the conduits 31is illustrated in Figure 5. The side wall of the housing is providedwith a pair of closely related apertures, and rubber grommets 38 or theequivalent are secured in the apertures. Each grommet is so constructedthat it may be prsssed and held in place by its own resiliency withportions engaging the opposite surfaces of the side wall of the housing.Each conduit is preferably of a slightly greater outside diameter thanthe inside diameter of the hole in each grommet as illustrated in Figure5 so that the grommet will resiliently bear against the conduit, andother portions will be pressed tightly into engagement with portions ofthe side wall housing so as to provide a connection which will preventfluid or foreign matter from entering the housing through the aperturesin the side wall of the housin or through the holes in the grommets. 1 tIn view of the foregoing, it will be apparent switch mechanism, saidswitch casing having an end wall, a housing enclosing the said electricswitch casing and switch mechanism, said housing having an end wall,aligned apertures provided in the end walls of said switch casing andsaid housing, means passing through said apertures for firmly securingsaid casing and the housing together, cooperating means provided on oneof the end walls, and means provided on one of the other end wallsinterengaging said cooperating means whereby to prevent rotation of.said housing in respect to said switch casing.

2. An electric switch construction including, an

open ended housing having an end wall, an electric switch disposed insaid housing, said switch ing means, said bearing means being providedwith a reduced extremity projecting through the said apertures and withits end flanged over and against the inner wall of the switch casing forpermanently securing the housing, casing, and bearing together.

3. Electric switch construction including, an electric switch casingcontaining conventional switch mechanism, said switch casing having anend wall, a housing receiving said switch casing and switch mechanism,said housing having an end wall, aligned apertures provided in the endwalls of said switch casing and said housing,

.means passing through said apertures for firmly securin said casing andhousing together, a pocket provided in the end wall of said casing, andmeans projecting into the pocket from the end wall of the housingwhereby to prevent rotation of said casing with respect to said switchhousing.

4. An electric switch construction including; an open ended housinghaving an end wall, an electric switch disposed centrally in saidhousing; said switch being provided with a casing having an end wallengaging the end wall of the housing; apertures provided in said endwalls; tubular bearing means having a reduced inner extremity projectingthrough the apertures and with its end flanged over and against theinner wall of the switch casing for permanently securing the housing,casing, and bearing together; means on one of said end walls cooperatingwith means on the other end wall preventing rotation of said casing withrespect to said housing; means for closing and sealing the open end ofsaid housing; means for closing oil an outer extremity of the tubularbearing; and means providing a seal seated in said bearing adapted toengage shaft means movable in said bearing.

HERSCHEL C. BOLLEY.

